CLASSIFICATIONS OF ORGANISMS

A science lesson
on classifications. Students will learn about Kingdom, Phylum, Class, Order, Family, Genus, and species, how to classify humans, and what these classifications mean. Includes printable
teaching reading comprehension lesson worksheets.

Suggested Grades:

4th Grade - 5th Grade - 6th Grade

Objective:By
completing this biology lesson, students
will learn about classifications, and in the process demonstrate their reading comprehension
skills, including reading strategies, inference,
literal meaning, and critical analysis.

Students should read the passage
silently, then answer the questions. Teachers may also use the text as
part of a classroom lesson plan.

Lesson Excerpt

There are many organisms in the world. Some organisms share characteristics, while others do not. That is why scientists have classified organisms into various groups. Each group shares similar characteristics. Ancient organisms that relate to modern-day organisms have been grouped similarly. This helps scientists to understand exactly how organisms have evolved over the centuries.

Biologists study both living and dead organisms in order to determine where the organisms should be classified. Based on the characteristics of the organism the biologist will decide which groups of classification the organism fits into. However, not all biologists agree with where an organism is classified. So, ultimately it is up to the biologist, who may consult other biologists, to determine the placement of organisms within a specific classification.

The languages that are used to classify organisms are Latin and Greek. This is because, in ancient times, almost all scholars and scientists spoke both Latin and Greek. Organisms are classified in the seven main groups. Every organism in the world that scientists know about has been classified into all seven groups.

Groups of Classification

The seven groups of classification are:

Kingdom

Phylum (Divisions)

Class

Order

Family

Genus

Species

The first level of classification is the Kingdom. This is the biggest unit of classification. The smallest, or most basic, level of classification is the species. You may know a species by a more common name such as a human, a fish, or an oak tree. Classification levels between Kingdom and species gets smaller in size, when moving from the top level down to the bottom. (continued...)